Questions tagged [snubber]
A snubber is a circuit used to suppress transient voltages in electrical circuits. It can include RC snubbers that comprise a resistor and a capacitor in series, often used for AC circuits, and also a diode used across relays and other inductive components to suppress their inductive 'kickback'.
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Is a flyback diode needed when using an RC snubber?
In order to minimize ringing when switching the mosfet, I had to implement an RC snubber circuit. Now, in that case, is the flyback diode still required?
Also, I measured with an oscilloscope the ...
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AOZ1284 SMPS - RC snubber needed?
I'm designing an IoT Edge gateway that I intend to take open source. It's essentially a motherboard with a SMPS and various peripherals (ADCs, digital I/O, RS-485, etc.) and hosting an Orange Pi Zero ...
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TRIAC Blows Off in Single-Phase Induction Motor Capacitor Switching Circuit
(Q2 is not populated)in above circuit the R11, R12 VALUE IS 360 ohm 2W, R10 is 39 ohm 2W and the c2 is 0.01uf 1000v fuse is rated 16A 250V, Q1 is BTA41600B, the above circuit use 80-100UF 250vac ...
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Snubber circuit design for a sensitive gate TRIAC
I am designing a snubber circuit for a TRIAC used to drive an RL load. The problem is that I do not know the exact inductance of the load.
The load is a resistance comprised of wrapped wire forming a ...
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RCD snubber loss in flyback converter
I have few queries in analyzing the curves. Below is the flyback converter with RCD snubber circuit and waveforms.
When the FET is turned ON, there is no primary current flowing through snubber as the ...
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Relay controlling DC motor welding shut
I am controlling a fairly large DC motor using a relay. The motor draws approximately 7A at 36V. I am controlling it with a relay rated at 110VDC, 50A. To protect against back-EMF, I placed a ...
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Correct Implementation of Flyback Diode, TVS Diode, and Snubber Circuit for Buck Converter?
I am fairly new to circuit design. I was wondering if I have correctly implemented the TVS diode (D8), flyback diode (D6) and the snubber circuit (R20 and C41) for this buck converter. I apologize in ...
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Purpose of this RSNUB
This image is from the schematic of an overvoltage protection regulator.
https://www.analog.com/media/en/technical-documentation/eval-board-schematic/1018babcsch.pdf
I'm trying to find out the ...
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Question on Turn-off Snubber Operation
I'm struggling to understand how this snubber circuit reduces power loss during the off time for this buck converter. Anybody able to explain it's operation / what is happening for each component ...
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Finding resistor and capacitor values for a snubber circuit to reduce diode's reverse recovery time
I'm trying to wrap my head around snubber circuits. I've read that the purpose of these circuits is to absorb energy coming from voltage spikes when a switch closes. We're currently studying snubber ...
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MOC3083 + replacing triac with 3Q one + no snubber
This is famous circuit from the MOC308x datasheet which many people use and refer to:
I have recently asked related question on the usage of the BT136.
I would like to understand how this circuit ...
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Snubber circuit for SPI clock and SPI MOSI
I am using the SPI interface to communicate with the MEMS sensor (ASM330LHH). My plan is to operate it at a 10 MHz speed.
The PCB is split into two parts, connected by cables. The distance between the ...
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Triac flickers when I apply main power
I am building an ESP32-based AC mains power switch by using TRIAC BT136-600D (common triac).
My first issue is my load didn't turn off the load (lamp) properly at 30%-40% brightness, and when triac ...
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Snubber design for a relay that controls a 30W AC fan
I am trying to switch a 30W, 230V AC fan and a LED strip with an Arduino from D11 and D12 pins. In my previous experience, the EMI generated while turning off the fan bricked my project within months ...
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Flyback converter sense resistor placement and wiring
I am designing my first ever Flyback converter. The Fsw = 100kHz. Peak primary current = 3.26A.
The converter has to fit in a very small space, so I'm making a lot of compromises. For example, I could ...
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RCD snubber circuit
I'm designing a timed fan switch using an 800V 25A (overkill) TRIAC with an RCD snubber circuit with 120VAC source. The circuit is shown at the TRIAC shut off at I_hold of 50mA. The load current at ...
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What paths can the induction spike from a relay controlling a Fan and Aircon unit take? How to problem solve it? What would you do?
Problem: I have an induction spike feeding back into my AirCon and Fan control project when the fan or Aircon is switched off. The program keeps running on the microcontroller but the spike ...
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Power MOSFET protection from inductive loads
I have a circuit which is a low side switch for a BMS. And because this a power board that is separate from the actual BMS, I don't the access to Batt+ line. (The Batt+ line is directly given to the ...
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RC snubber causing latch in relay
I'm driving an RT314730 relay directly with an MOC3063:
simulate this circuit – Schematic created using CircuitLab
The problem is when SW1 is open the relay latches. I tried 10nF instead of ...
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Is this circuit sufficient?
Firstly I am sorry for this bad drawing but I just got it from the internet.
Secondly I'll give a brief idea about the project it is a static switch would be used to drive general loads (inductive and ...
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Snubber circuit protection
I am trying to understand how to implement snubber circuit protection as I have seen different circuit diagrams, I am lost.
Image source: Homemade Circuit Projects - Prevent Relay Arcing using RC ...
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Two switch flyback converter MOSFETs voltage stress
I am exploring and experimenting the two switch flyback converter. I have a doubt, in this two switch flyback converter configuration, two MOSFETs are connected in series with sandwiched primary coil ...
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Relay + RC Snubber to switch contactor - parasitic voltage?
I have designed yet another custom PCB with an ESP32 and some relays that I will use for some IoT projects.
I am using one of these relays to switch a 230 V AC contactor which then switches a 230V AC ...
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MOC3041 typical SSR circuit, when snubber is applied, triac never turns off
I am trying to make this circuit:
I got reference from this site, which is very useful, thanking them for info;
https://components101.com/ics/moc3041-zero-cross-triac-driven-optoisolator
Despite all ...
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LTspice snubber simulation
I'm attempting to simulate a bi-directional snubber to limit the peak voltage when switching off, as shown in the picture below. The resistance of R2 changes from 1 mΩ to 1 MΩ when a current of 1 kA ...
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Driving 2-way synchronous motor valve with SSR
I need to control a 2-way 3-wire 230VAC synchronous motor (6W) driven HVAC valve with SSR. (This is a custom thermostat with heating-cooling valve controller).
The valve internal circuitry is ...
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Is this RC Snubber functional?
I had made this circuit which is basically works somehow as a UPS (when there is a power failure from the mains (220 VAC) the inverter line turns on and keeps the load on) and yes I had tested the ...
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Do I need a snubber in a snubberless triac?
I am trying to make this circuit and using the Triac as a switch. I am using in this one a BTA06, although I will upgrade it to a BTA12 so it can handle 220 V 1000 W easily. It will be implemented in ...
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Is it superfluous to place a snubber in parallel with a diode by default?
I'm a VHDL guy for work, and play with power converters on the weekends so please forgive if this question is dumb.
When using MOSFETs, IGBTs, or SCRs in power converters, it is typical to see ...
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RC Snubber Design Hint for 3 phase AC-AC PWM Chopper
Im trying to design a 3 phase Ac-Ac Pwm Chopper, I'm having difficulty designing the snubber network for the mentioned topology.
Now I tried testing this circuit on bench , with my IGBT snubber values ...
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How to put a decent snubber to the MOSFET?
I am trying to make a soft starter for an inverter to make the turn on process as a yield curve like the one in the photo:
so I used this circuit :
however, the problem is still visible in the turning ...
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Driving a 12V DC small pump with a MOSFET
I need to drive a small immersion pump with a 5V output of a microcontroller. I found easy to find this mosfet: https://www.sparkfun.com/datasheets/Components/General/RFP30N06LE.pdf
By looking at the ...
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How is an RCD snubber different from an RC low pass filter?
The RCD snubber is used in flyback SMPS designs where AC-DC conversion is carried out. I know that a snubber circuit is used; its purpose is to filter transients. According to my understanding, the ...
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Should a flywheel diode be installed for SSR with AC load and DC input?
I have a solid state telay (SSR) that switches a 240 V AC appliances's input based on a 24 V DC input. The relay takes 24 V DC input and controls a 240 V AC connection.
I understand that for DC loads, ...
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How to mitigate excessive ringing in VDS and VGS
I have a few questions regarding my measurement results in the lab for a double pulse test setup. There are three issues which I want to mitigate
.
At turn-on interval, there is excessive ringing in ...
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RC snubber network not protecting IGBT
I'm working on an electromagnetic accelerator project but I'm having trouble protecting my IGBTs that switch current through the coils. Here's the schematic:
C1 gets charged to around 250 V (In my ...
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Interference from compressor pressure switch
In my CNC machine, I have a small air compressor and a spindle motor VFD connected in same 240 VAC outlet.
Whenever the compressor switches on or off, the VFD reports "OC-o" error. According ...
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Snubbing an H-bridged motor
Mostly a follow up to https://electronics.stackexchange.com/questions/175778/rc-snubber-across-switch-or-inductor…
I've seen RC or RCD snubbers across the switching MOSFETs (and these damp the dV/dt ...
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Designing a simple controller for a hot plate
I have a hotplate with a TS port meant for an external temperature control unit. The manufacturer's customer service told me that this port is not connected to anything internally in the model I own. ...
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PWM driven 24 V fan noise issue
I have a weird issue with a 24 V blower fan. We are driving it with an N-channel MOSFET at a PWM freq of 12 kHz. It has a periodic artifact that appears about 230 Hz or so.
Observable behavior ...
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RC snubber not working when R > 0
I am running a 40 Ohm heating element directly connected to a 180 Volt, 8 A (@ max power) PV array. I am trying to use an RC snubber to protect the switch. I calculated the R and C values using this ...
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What is a "snubberless" TRIAC? How does it compare to a standard device?
I was searching for a TRIAC to be used as part of a pre-charge circuit for large DC link capacitors, and found one (T435T-600FP) that is described as "snubberless". An on-line search did not ...
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Sizing a RC Snubber - microcontroller restarting when switching off an inductive load
I'm trying to drive an 220 V solenoid water valve with a relay, but I'm having problems: when I turn off the solenoid, the microcontroller reboots.
I believe the source of the problem is the spike ...
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What is the function of varistor in this design [closed]
Came across this on internet. The description mentioned this module help prevent relay stick to the contact. Please explain why varistor need to be included in the design if it is to connect in ...
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Inverter MOSFET Snubber: RC or Schottky diode?
I've researched this question and found a lot of theory, but not much practical anecdotal experience. I would like to hear from those with physical knowledge of this.
I've constructed a transformer ...
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RLD + RC Snubber for MOSFET
I'm currently making a DC-DC SMPS power supply that converts 331VDC (rectified from 240VAC) to 60VDC with a maximum output current of 10 amps. I've asked once on this forum about a general problem on ...
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Snubber circuit for electromagnet
I have run into the same problem described here and here, when I added diode to electromagnet. Basically, the magnet still holds with about 20kg force several minutes after removing power. The ...
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What causes spikes on a primary push-pull transformer with good snubber and tvs?
I am repairing 8 second-hand microgrid inverters from 2013.
The internal structure is a push-pull sinusoidal current generator. DC input 12 to 28V, 250W. The primary side suffers from a design problem....
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Noise suppression circuits for a 120VAC motor
I am building a circuit for a relay that controls power to a 1000 watt pump motor. I want to do what I can to reduce noise and failure of the circuits from transients etc.
Here is my schematic:
I ...
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Decoding SPICE Model for onsemi SZ1SMB5939BT3G 30V Zener
I would like to model using the onsemi 1SMB5936BT3G (30V Zener Diode) SPICE model, but the SPICE model is not acting as I am expecting. Built-in LTspice Zeners clamp the kickback no problem but the ...
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